The need to effectively see a target and aim a weapon in the direction of the target is well recognized. Auxiliary devices to facilitate illuminating a target or aiming a weapon are known. Examples of known auxiliary devices include scopes, visible and infrared illuminators, laser pointers, combined illuminator/laser pointer devices, night vision devices and infrared imagers. For convenience, these (and other) devices are generally referred to herein as auxiliary devices. These auxiliary devices are often mounted to weapons having rail mounting systems with a certain profile, for example a rail profile consistent with MIL-STD-1913. Although these rail profiles have tolerances, these tolerances can vary enough to cause auxiliary devices to not fit properly and therefore not maintain boresight after continued use.